Proof standards and statements

Absolute proof is probably only attainable in abstract disciplines like Mathematics and Logic. So when we use the word ‘proof’ in the real world of natural science, and of history and genealogy, the focus is rather on the use and quality of evidence to support a hypothesis, always acknowledging that conclusions are open to change when new evidence is found.

1. The Genealogical Proof Standard

The American Board for Certification of Genealogists is a certifying body for genealogists founded in 1964 by Fellows of the American Society of Genealogists.1 In 2014 they published The Genealogical Proof Standard (GPS) with its five elements:2

2. Proof statements

This Archive employs the concept of a ‘proof statement’3 to mean the presentation and critical analysis of the evidence to support a conclusion. Some use the term ‘proof summary’ or ‘proof argument’. They have no set format in this Archive and vary with each case; minimally comprising the simple presentation of a fact, like the date of a marriage from its certificate. More complex ones contain some analysis and/or synthesis of a cluster of facts or circumstantial evidences, and therefore can be strong or weak. All proof statements in this Archive are open to re-evaluation if new evidence arises, and your challenge to their conclusions is welcome. The Archive doesn’t claim that its findings are absolutely correct, just the least wrong at that point in time, and therefore always subject to improvement. If you see any proof statements in this Archive that seem insufficiently established, or biased, do get in touch. Nothing in this Archive is designed to deceive.

3. Negative proof

“Negative proof: A term [or method] much used in genealogical research. It denotes the attempt to prove that a name found in a parish register, etc. is the one being sought by searching all other records in the neighbourhood to make sure that no one else of that name is recorded.”4 As such, it can contribute to a good proof statement, especially when backed up by the five elements of the Genealogical Proof Standard. If reasonably exhaustive research has been conducted into all other records in the neighbourhood and the evidence is presented accurately and interpreted skillfully, then negative proof will provide a satisfactory proof statement.

Some discussions of negative proof in different disciplines cite the example of “the sound of the dog not barking”5 and the maxim “absence of evidence is not evidence of absence”. These can lead to both reasonable and unreasonable arguments, so in genealogical methodology the wider context is a more practical guide or arbiter than the philosophical or abstract purity of an argumentation. In the story, the sound of the dog not barking may not have been proof beyond reasonable doubt on its own, but it was accompanied by a number of other items of circumstantial evidence. Each of these were similarly not clinching evidence on their own but together they solved the case beyond doubt. Similarly, in genealogical research the negative proof of the absence in other records in the neighbourhood of anyone else of the same name as the one being sought, may not be conclusive on its own, but along with other circumstantial evidence can combine to produce a proof statement beyond reasonable doubt.

4. Hearsay and speculation

Pure evidence-based genealogy is probably unattainable, and we have to acknowledge that a good deal of the evidence we find and use is hearsay, strictly speaking. Most of the information on a birth, marriage or death certificate, for instance, is normally supplied by an interested party and can be subjective. Did Thomas Brockett of Lambeth give his father’s name truthfully on his marriage certificate?

Further up the scale of unreliability are family stories. How accurate were the stories your grandmother told you about her grandparents? Did her family really lose contact with uncle Jim because “he went to Australia”? On the other hand, older relatives’ reminiscences and letters can be invaluable sources of insider information not to be found elsewhere. When they can then be backed up by documentary evidence they often open up dead ends.

Census records are usually considered more objective, but you could argue that even they are secondary sources—the enumerators were only recording what the people in the household wanted to tell them. Do we dismiss them as hearsay, or would such evidence be permissible in a court in certain circumstances?

Evidence from the likes of actual parish records, land transactions and court cases, as opposed to transcriptions of them, is probably the nearest we will get to objectivity, but these aren’t always available. Does that mean we have to give up? No! Absolutely not! Genealogy isn’t a court of law. Everything doesn’t have to be proved beyond reasonable doubt. Proof statements can be strong and weak. A weak one may be the best we can produce. It is still useful—we just have to acknowledge that the information we are working with may not be true, and above all remain open to new evidence that might conflict.

And what about speculation? Is there a place for it in genealogy? Why not, if it is treated with caution. Guessing without a firm factual basis sits at the very weakest end of proof statements, but provided it is flagged as such it can still contribute to a proof statement of sorts. Imagination can be enlightening, narrative accounts can bring the past to life. But again, as soon as something disproves the speculation, it must be discarded.

Each case in genealogy has to be judged on its own merits, and if we measure them against the Genealogical Proof Standard we will be able to tell the bad ones. Strong and weak proof statements are both acceptable, the strong more so than the weak. What isn’t acceptable is a bad one.

6. DNA

With genetic genealogy we have an enhanced, more scientific, kind of proof, which combines DNA testing with genealogical and historical records, and typically makes use of large databases to identify matches.7 It can also fill gaps in the documentary evidence and even override it. And as testing techniques develop this will probably be a vantage point from which future genealogists look back on our attempts to gather documentary proof with some amusement. It has already filled several documentary gaps in Broket research and will fill more. Please consider joining our DNA project!